Panel 2

Close up on 'Socks User Manual' where you can see 'FIGURE 1: SOCKS' and a picture of a sock, and on the other page 'FIGURE 2: NOT SOCKS' with a picture of Beaver, Steve, a bee and a windmill.
Monster2: "Let's see now... Oh my!"

Panel 3

Monster2: "They are not socks at all!"
Monster1: "You lied to us? For shame! Take them to the detention centre!"
Steve: "I'm very disappointed in you Beaver."
[To be Cont'd.]

Fun Facts

Beaver is a liar.

Aliens who steal left socks are not very bright, but very polite nonetheless.

Socks often do not come with a manual at all.

In Panels 2 and 3, we can see Gruglarr clearly has more than two 'arms.' However, The other alien appears not to have extra arms.

In the Socks User Manual, Beaver and Steve are shown in the exact positions that they appear to be standing in at the time the alien checks their sockiness-status.

Beavers, lizards, bees and windmills are NOT SOCKS

References

The bee in the book looks very similar to the Bee in Comic 38. Probably because it's a bee.